End of the Day: S&P 500 up 4.5 to 1,433.56; Dow Jones up 69.1 to 13,323.36; Nasdaq up 0.5 to 3,104.53

The following is a brief summary of events moving markets today:

Once again, Moody's is dangling a downgrade in front of the U.S., threatening to use it if debt issues don't start shaping up. And soon.

Moody's said the U.S. would lose its top-notch rating if Congress repeals spending cuts and tax increases without large-scale deficit-reduction measures.

Last week, government debt hit $16 trillion last week, shy of the $16.394 trillion limit set by Congress. In total, the U.S. has run a $1 trillion deficit for the last four years, setting the upcoming election -- which is less than two months away -- to be much more exciting.

Facebook (Nasdaq: FB) CEO Mark Zuckerberg issued the first interview since the Company went public on May 18th. Some comments from the interview include:

Services aren't made to make money;

Six months ago, Facebook was in a pretty bad place on mobile;

He thinks Facebook will make a ton of money on mobile;

He called recent stock performance disappointing;

Sees making more money on mobile than on desktop;

People at Facebook are used to controversy and the stock fluctuations aren't the first headwinds the company has faced;

More people using mobile web Facebook than on Google's (Nasdaq: GOOG) Android and Apple's (Nasdaq: AAPL) iOS combined;

The biggest mistake was betting on HTML5;

Facebook is not building it own smartphone, due to it not being the right strategy;

Facebook does a billion search queries per day;

The goal is to integrate Facebook into many devices; and

The Instagram deal came about as the founders were already using Facebook's platform and the two began working together to further develop integration. Eventually, Instagram founders began to get nervous about focusing on one sole company as a crutch and Zucks suggested the the two should become one. Bam, done deal.

♪"He's got Legg's, and he knows how to use them"♫...to walk out the front door: Legg Mason (NYSE: LM) CEO and Chairman Mark Fetting will retire on October 1st, according to a release out earlier.

Global distribution head Joe Sullivan will become Interim CEO at that time as the Board conducts the search for a new CEO. For interested parties:

Citi also issued an update later in the session, seeing a non-cash third-quarter 2012 GAAP charge of $2.9 billion. For more color, click here.

Key executive changes could unlock more value: Ford (NYSE: F) is further solidifying succession plans. According to reports out late Tuesday, Americas president Mark Fields may become the automaker's Chief Operating Officer. The move would also line Fields up to succeed current CEO Alan Mulally when Mulally decides its time to retire.

Fields has been with Ford for 23 years and was integral in realigning Ford's North American ops, shifting the segment from a money-losing cause four years ago to one that is solidly profitable today.

No official announcement has been made by Ford.

Don't be a tattletale...unless you can make a boatload from it: One former UBS banker -- who was an informant to the IRS in unearthing an offshore account scandal a few years ago -- was awarded $104 million today. If it makes you feel better, he's still in jail for conspiracy of fraud.

Just like that, the Treasury cracks a smile. We think: The U.S. Treasury priced its 553.8 million offering of American Int'l Group (NYSE: AIG) shares at $32.50 each. AIG agreed to purchase approximately 153.8 million shares of AIG common stock in the offering at the initial public offering price for an aggregate purchase amount of approximately $5 billion. Proceeds from the sale were $20.7 billion with the U.S. now holding about 15.9 percent of AIG.

Later in the session, AIG CEO Bob Benmosche said the the insurer might reinstate a dividend next year.

Click here to go to Streetinsider's Full News Feed and never miss a beat!